Chapter V ferromagnetic materials

In the present section, attention is confined to ferromagnetic materials that are nonmetallic. The materials dealt with are characterized by a resultant spontaneous magnetization that ordinarily is due to an uncompensated antiferro-magnetism. In Néel´s terminology substances of this type would be described as “ferrimagnetic”. We shall make no particular effort to employ this special terminology, rather we shall regard the term ferromagnetism as a general one which includes ferrimagnetism as a sub-class.